26 KB235 KB26 KB199920252005Vekteris, Vladasštevilka:2letnik:518 stranistr. 95-102ISSN:0039-2480COBISSID:8164123URN:URN:NBN:SI:doc-DJTWA1RAenAssociation of Mechanical Engineers and Technicians of Slovenia et al.Zveza strojnih inženirjev in tehnikov Slovenije et al.Strojniški vestnikanalize eksperimentalnebrušenjedeformacijemehanske lastnostinapetostipostopki brušenjasimuliranjePrehodni pojavi pri postopku brušenja| Transient phenomena in the grinding process|Local contact displacements resulting from the elastic deformation of the tooland the blank, were studied using the finite-element and by experiments. Graphical and analytical expressions for the cutting force, with harmonical and stochastic components, were obtained. Previously published research on thebehaviour of the contact between the grinding wheel and the workpiece has been based, on the assumption that the contact deformations represent a directfunction of both the normal and the tangent forces acting on the wheel or its grains during the grinding process, without taking into account the attrition and breaking of the grains. This paper covers the procedure for researching and graphically representating transient processes and the patternof the abrasive grainsć destruction within the contact zone under impulse loads, which is based on the method of finite elements and the resultsof a high-speed circular plunge-grinding experiment. The above-mentioned method can be applied to elastic, inelastic, plastic and othernonlinear materials machined by grinding. To introduce the nonlinear properties of the material in the experiment, the modulus of the volume and the modulus of the shift in the contact zone between the grinding wheel (grade24A12INI28E5) and the workpiece (steel 45) are simulated by three-parametric elements. The presented method makes it possible to calculatetransient stress and deformations during high-speed circular plunge grinding and to study the destruction of abrasive grains in a two-dimensional medium with indefinite boundaries and nonlinear characteristics. The present research is aimed at finding out the influence of transient phenomena on the structure of the cutting force during the process of grindingLokalne stične premike, ki so posledica elastičnih deformacij orodja in obdelovanca, smo proučevali z uporabo končnih elementov in s preskusi. Izdelali smo grafične in analitične prikaze rezalne sile s harmoničnimi in stohastičnimi elementi. Predhodno objavljene raziskave stika med brusilnim kolesom in obdelovancem temeljijo na predpostavki, da predstavljajo stične deformacije neposredno funkcijo normalnih in tangencialnih sil, ki med postopkom brusenja delujejo na kolo oz. njegova zrna, brez upostevanja obrabe in lomljenja zrn. V prispevku smo, s pomočjo metode končnih elementov in preskusa kroznega polirnega brusenja z velikimi hitrostmi, opisali postopek raziskave in grafično prikazali prehodne pojave in vzorec uničenja brusilnih zrn znotraj stične zone kot posledico impulznih obremenitev. Prej omenjeno metodo lahko uporabimo pri proznih, togih, plastičnih in drugih nelinearnih materialih, ki jih obdelujemo z brušenjem. Uporabo nelinearnih lastnosti materiala, modul prostornine in modul pomika v stieni coni med brusilnim kolesom (vrsta 24A12INI28E5) in obdelovancem (jeklo 45), smo pri preskusu simulirali z uporabo tri-parametričnih elementov. S predstavljeno metodo lahko izračunamo prehodne napetosti in deformacije med krožnim polirnim brušenjem z velikimi hitrostmi ter proučujemo uničenje brusilnih zrn na dvorazsežnem modelu z nedoločenimi mejami in nelinearlnimi značilnostmi. Namen predstavljene raziskave je določitev vpliva prehodnih pojavov na sestavo rezalne sile med postopkom brusenjaTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaUniverza v Ljubljani, Fakulteta za strojništvo